Incorporating RX5 as Wave Editor

I think as of RX4, using "RX Connect" is the preferred method.

The problem you are having is with shared audio drivers.  Some audio drivers/sound cards are more flexible than others for that.  If you can't get RX to share the ASIO driver with Sonar, you might want to try setting RX to use the WDM driver.  Sometimes that can share with Sonar and you don't really need low latency in RX.  It all depends on your sound card and driver.  I've had lots of luck sharing with my very old Focusrite Saffire, but other cards/drivers will be hit or miss.
 
I'd also recommend using the tool Cactus Music points out.  With RX as a wave editor you need to specify the RegionFlag to off, otherwise you get this silly error every time it starts up.

RX Connect is the way to use it with Sonar or any other compatible DAW.

Keith, in the statement below from the iZotope site it's clear for me that this is the way to use RX as a wave editor in any compatible DAW. I only use the VSTs but look at this thread, specially #14 e #15:
http://forum.cakewalk.com...-Connect-m3089117.aspx

RX Connect

Integrate a quick workflow between your DAW/NLE and RX Audio Editor to utilize all the repair/enhancement modules needed to cleanup production audio.  For Pro Tools RX Connect now supports clip-by-clip and handles which preserves the boundaries of clips, so you can conform to future picture changes with ease, making RX Audio Editor a natural extension of Pro Tools.  RX Monitor enables you to monitor your audio from the RX Audio Editor application through your host application (i.e. Pro Tools, which does not allow other applications to use their hardware simultaneously). 

I'm with superdan...... I get RX5 to open OK from the tools menu, and/or by using the RX Connect but have not yet figured out how to get a rendered file back into the SONAR track.  (Have not spent a lot of time with it either).  One of these days......

Yesterday, I gave it a try and it worked for me.  I inserted RX connect in the fx bin, selected the audio clip, opened RX connect (it starts to retrieve the audio clip), clicked in "Repair" then RX opens the clip in its pool, made some tweaks and clicked in the Sonar tab to send it back.  Although I selected only the clip, RX brought the entire track to the pool but I don't think it's a problem at all. Well, I'm gonna do more tests but, at least, I think it works ok.

RegionFlag set to 0 is off.
 
You can read more about this in this thread:
http://forum.cakewalk.com/FindPost/3221385
 
If you are getting an error from RX with a caption of "Can't open use session data folder" and text like "The currently selected session data folder cannot be used.  Open preferences, and choose a new session data folder" that is the region flag problem. 
 
But if you error messages have anything to do with sound drivers or ASIO, that error is your audio card doesn't like sharing its drivers with two applications.  The only way to fix that (if it can be fixed at all) is very specific to the drivers/sound card you are using.  There is an option in the Sonar preferences about sharing that might help (though it works so rarely I'd not get my hopes up).  When that doesn't work you can sometimes set the external application (in this case RX) to use the WDM/MMO/Windows native drivers instead of ASIO.  So let Sonar have the ASIO drivers and the external app use the native windows driver.  That kind of setup is a very fragile and unlikely to be reliable but I have seen it work.  Those are the only two generic work arounds I know of.  Everything else is driver/audio card specific settings and other configuration magic.

I believe that is the case. Sharke just asked similar with using Adobe Audition, and the above is also what I observe when making destructive changes. I "believe" the above RegionFlag reference is for programs which can see a "clip" discretely (i.e., "Region FX") inside the underlying wav file, and that both older versions of RX and Audition do not have this capability (so get the entire wav file passed to them instead).

I got RX Connect to work with RX5
 
http://forum.cakewalk.com/Izotope-RX-5-and-Sonar-m3505341.aspx
 
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